1. Field of the Invention
The present invention generally relates to image forming apparatuses, image forming methods, and computer-readable storage media that store a program which, when executed by a computer, causes the computer to perform a process in accordance with the image forming method.
2. Description of the Related Art
Conventionally, when a Portable Document Format (PDF) direct printing is performed using pre-punched paper, an image may be printed in a region corresponding to holes in the paper and cause a portion of the image to drop out at the holes. For this reason, the image to be printed is subjected to a processing such as reduction, in order to adjust a print position of the image on the paper.
For example, a Japanese Laid-Open Patent Publication No. 7-314843 proposes a method of printing the image that is adjusted to fit within the area of the paper, by preparing a plurality of rectangular graphic data representing printing regions. This proposed method derives a magnification or reduction with which output information that is edited for a predetermined paper size is to be printed within a paper size based on the selected rectangular graphic data.
However, when images of different document sizes are to be printed on the same paper size according to the proposed method described above, even if it is possible to derive the magnifications for the images of the different document sizes in order to print the images within a certain paper size, it is impossible to print the images by adjusting the position of each image to a central area of the paper having the certain paper size.
In other words, in order to arrange the position of each of the images of different document sizes to the central area of the paper having the certain paper size, it is necessary to compute image adjusting parameters for arranging the image to the central area of the paper, and to input a moving amount of the image by a printer driver, for each print job. As a result, the proposed method described above may not be convenient for use by a general user.
Next, a description will be given of an example of a conventional print position adjusting method, by referring to FIGS. 1 through 5.
FIG. 1 is a diagram illustrating images of different document sizes Ds1 and Ds2 with respect to a predetermined paper size Ps. As illustrated in FIG. 1, in order to print the images of the different document sizes Ds1 and Ds2 to fit within the area of the paper having the predetermined paper size Ps, the user in this example must input the reduction of each of the images of the different document sizes Ds1 and Ds2 and the moving amount of the images to adjust the position of each image to the central area of the paper having the predetermined paper size Ps, for each print job.
FIG. 2 is a diagram illustrating the images of the different document sizes Ds1 and Ds2 that are reduced by the same reduction. FIG. 3 is a diagram illustrating a reduced image Ds1r of the document size Ds1 adjusted by a certain moving amount to a central area of the paper having the predetermined paper size Ps, and a reduced image Ds2r of the document size Ds2 adjusted by the same certain moving amount as the reduced image Ds1r. 
In FIG. 2, the user inputs the reductions of the images of the different document sizes Ds1 and Ds2 so that the reduced images Ds1r and Ds2r fit within the predetermined paper size Ps. Then, the user computes the certain moving amount or, parameters, for adjusting the position of the reduced image Ds1r to the central area of the paper having the predetermined paper size Ps. However, if the certain moving amount that is computed for the reduced image Ds1r is also used with respect to the reduced image Ds2r, the reduced image Ds2r will not fit within the predetermined paper size P2, and an image portion Ds2d indicated by hatchings in FIG. 3 will drop out from the printed image on the paper.
Accordingly, when the same setting related to the magnification or reduction and the moving amount is used with respect to all of the print jobs, a portion of the image may drop out and not be printed on the paper, depending on the document size. For this reason, when printing the images having different document sizes while centering the images to the central portion of the paper, the user must carry out a troublesome operation of computing the moving amount of the image for achieving the centering of the image, and setting the computed moving amount, with respect to each print job.
FIG. 4 illustrates an example where the reduced image Ds1r is moved to the central area of the predetermined paper size P2 by the centering. As may be seen from FIG. 4, the user must compute the moving amount of the reduced image Ds1r, including a position adjusting length x1 in an X-axis direction and a position adjusting length y1 in a Y-axis direction using a bottom left corner of the predetermined paper size Ps as the origin, and perform a positional adjustment of the reduced image Ds1r based on the computed moving amount, in order to arrange the reduced image Ds1r to the central area of the predetermined paper size Ps.
FIG. 5 illustrates an example where the reduced image Ds2r is moved to the central area of the predetermined paper size P2 by the centering. As may be seen from FIG. 5, the user must compute the moving amount of the reduced image Ds2r, including a position adjusting length x2 in the X-axis direction and a position adjusting length y2 in the Y-axis direction using a bottom left corner of the predetermined paper size Ps as the origin, and perform a positional adjustment of the reduced image Ds2r based on the computed moving amount, in order to arrange the reduced image Ds2r to the central area of the predetermined paper size Ps.